In this Grade 3 lesson from Science: A Closer Look, Chapter 3, students explore how natural disasters such as floods, droughts, and wildfires, as well as diseases, cause sudden changes in ecosystems. Students learn key vocabulary including population, community, and endangered, and investigate how living things respond to environmental changes by migrating, adapting, or facing population decline. The lesson uses a hands-on plant experiment to reinforce cause-and-effect thinking about how too much or too little water impacts living things.
Section 1
Disasters Transform Environments Suddenly
Natural disasters like floods and droughts dramatically change environments. Floods wash away soil and plants, while droughts dry up water sources. Wildfires and diseases can also drastically alter habitats for living things.
Section 2
Living Things Respond to Environmental Changes
When environments change, organisms respond in three main ways: they migrate to new habitats, adjust their behavior to survive, or use special adaptations. Those unable to adapt or move may die.
Section 3
Communities Feel Ripple Effects from Changes
Changes affecting one population impact entire communities. If prairie dogs disappear due to disease, predators lose food sources, while other animals lose homes. Some species may benefit as new opportunities emerge.
Section 4
Species Become Endangered When Environments Shift
Organisms become endangered when unable to adjust to environmental changes. Human activities like hunting and habitat destruction threaten species like Bengal tigers and pandas, while climate shifts endanger plants like Saharan cypress trees.
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Section 1
Disasters Transform Environments Suddenly
Natural disasters like floods and droughts dramatically change environments. Floods wash away soil and plants, while droughts dry up water sources. Wildfires and diseases can also drastically alter habitats for living things.
Section 2
Living Things Respond to Environmental Changes
When environments change, organisms respond in three main ways: they migrate to new habitats, adjust their behavior to survive, or use special adaptations. Those unable to adapt or move may die.
Section 3
Communities Feel Ripple Effects from Changes
Changes affecting one population impact entire communities. If prairie dogs disappear due to disease, predators lose food sources, while other animals lose homes. Some species may benefit as new opportunities emerge.
Section 4
Species Become Endangered When Environments Shift
Organisms become endangered when unable to adjust to environmental changes. Human activities like hunting and habitat destruction threaten species like Bengal tigers and pandas, while climate shifts endanger plants like Saharan cypress trees.
Book overview
Jump across lessons in the current chapter without opening the full course modal.
Continue this chapter